炭化水素活性化および機能化のための硫化ジルコニアの電子性オルガノイリジウム (III) ピンカー複合体
Zoha H Syed1, David M Kaphan1, Frédéric A Perras2
1Chemical Sciences and Engineering Division , Argonne National Laboratory , Lemont , Illinois 60439 , United States.
Journal of the American Chemical Society
|March 23, 2019
まとめ
硫酸ジルコニアでサポートされた新しいイリジウム触媒は,C-H結合機能化とオレフィン水素化において高い活性を示しています. この単一場所の触媒は,反応性を高めるため,均質と異質の利点を組み合わせています.
科学分野:
- 有機金属化学
- 異質な触媒
- 表面科学
背景:
- シングルサイトサポートされた触媒は,同質的および異質的な触媒の利点を結合します.
- 触媒の設計には,金属と支柱の相互作用を調査することが重要です.
- 炭化水素の機能化のために利用された以前の作業 (dmPhebox)
研究 の 目的:
- 硫化ジルコニアの単一サイトサポート (dmPhebox) Ir (III) 触媒を合成し,特徴づけること.
- C−H結合機能化および水素化反応におけるサポートされた複合体の触媒的活性を評価する.
- 硫酸ジルコニアのサポートが触媒の性能を調節する役割を理解する.
主な方法:
- 硫化ジルコニアに (dmPhebox) Ir (III) 複合体の化学吸収.
- 拡散反射赤外線フーリエ変換スペクトロスコーピー (DRIFTS),DNP強化固体NMR (SSNMR),X線吸収スペクトロスコーピー (XAS) を使用した特徴付け.
- アルカンの脱水とオレフィンの水素化に対する触媒試験
- 反応機構を調査するための密度関数理論 (DFT) の計算.
主要な成果:
- 硫化ジルコニアに (dmPhebox) Ir (III) を成功裏に挿入し,イリジウム中心にカチオンの性質を与える.
- アルケンの脱水化を含む,電離性C-H結合の機能化において高い触媒活性が観察された.
- 支持する触媒によって触媒性オレフィン水素化の促進
- DFT計算では,β-Hの除去に対する活性化バリアが低いことが示された.
- シリカで支えられた同型複合体は,同様の条件下で活動を示さなかった.
結論:
- 硫酸ジルコニアは,高活性単一サイトイリジウム触媒を作るのに有効なサポートです.
- サポートされたイリジウムセンターのカチオンの性質は,C-H機能化の反応性を高めます.
- 硫化ジルコニア基材の独特な性質は,観察された触媒性能にとって極めて重要です.
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